Instructions
Bring the controller back to its place of purchase if you start experiencing problems right away. There's no sense in taking the guitar apart and trying to fix it if the retailer can just replace it with a new one.
Take the guitar apart to check wire connections, if the fret buttons short out or become unresponsive. Sometimes the wires to the fret buttons can develop a weak connection to the circuit board. This can sometimes be solved with a soldering iron, or strategic placement of electrical tape.
Try adjusting the motion sensor, if your guitar is acting unresponsive. Take off the back of the guitar and locate the motion sensor at the bottom corner. Loosen the two black screws on the sensor, and try a very slight clockwise rotation. Re-tighten the screws and replace the back cover.
Get some elastic bands to hold the whammy bar in place, if it loses its spring. Unresponsive whammy bars can sometimes be remedied by placing a rubber band on the inside or outside of the controller.
Consider purchasing a new controller if all else fails. Sometimes things just go kaput for whatever reason. If you've done everything in your power to remedy the situation with no results, it might be time to lay your axe to rest. Try a wireless controller this time around, and cheer yourself up by customizing it and making it your very own.